Make sqfs_tree_node_get_path more robust

Test against various invariants:
 - Every non-root node must have a name
 - The root node muts not have a name
 - The name must not be ".." or "."
 - The name must not contain '/'
 - The loop that chases parent pointers must terminate, i.e. we must
   never reach the starting state again (link loop).

Furthermore, make sure the sum of all path components plus separators
does not overflow.

Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>

1 files changed, 3 insertions, 3 deletions

diff --git a/bin/sqfs2tar/write_tree.c b/bin/sqfs2tar/write_tree.c
index d4f8366..1c19a5a 100644
--- a/bin/sqfs2tar/write_tree.c
+++ b/bin/sqfs2tar/write_tree.c
@@ -102,9 +102,9 @@ static int write_tree_dfs(const sqfs_tree_node_t *n)
 			return 0;
 		}
 
-		name = sqfs_tree_node_get_path(n);
-		if (name == NULL) {
-			perror("resolving tree node path");
+		ret = sqfs_tree_node_get_path(n, &name);
+		if (ret != 0) {
+			sqfs_perror(NULL, "resolving tree node path", ret);
 			return -1;
 		}